I agree about the "$XXX" style appraisals, to me that says "I really have very little idea what the domain is worth".

However are some obvious errors in this article,

".org names aren't worth much at all unless they are obviously useable for a nonprofit organization." - that view died years ago I think.

".info is the least valuble of the six extensions we've reviewed." - Have a look at dnjournals sales data for the last year or so. .info sales on average are substantially higher than .biz and .us.